Propellant compositions



United States Patent 3,103,782 PROPELLANT COMPOSITIONS George A. Olah and Stephen J. Kuhn, Sarnia, Ontario, Canada, assignors to The Dow Chemical Company, Midland, Mich, a corporation of Delaware No Drawing. Filed Nov. 17, 1960, Ser. No. 69,811 2 Claims. (Cl. 60-35.4)

This invention relates to propellant compositions and more particularly to propellant compositions useful in the propulsion of rockets.

In the rocket propellant field elementary fluorine in the liquid state has been proposed as an oxidizer to be used in conjunction with fuels. For example, a combination of fluorine and hydrazine is considered one of the most powerful rocket propellant compositions. However, liquid fluorine presents many problems in handling because of its high reactivity and toxicity.

It is the principal object of this invention to provide safe efficient fuels and oxidizers whose interaction will result in the high energies normally associated with the interaction of elementary fluorine and such fuels as hydrazine. Another object of the present invention is the provision of a propellant comprising a non-hypergolic fuel and a solid source of fluorine. Other objects will become apparent hereinafter.

We have now discovered certain solid complex fluoride compounds which possess excellent hypergolic properties when interacted withconventional fuels.

OXIDIZERS After an investigation, suitable sources of fluorine we prefer to employ are the solid complex fluoride compounds KBrF KIF SbC-lF AsCIF and AsBrF We have found that the interaction of the aforesaid complex fluoride compounds produce large volumes of gases when interacted with conventional fuels hereinafter set forth.

FUELS The fuels we have found hypergolically operable with the complex fluoride compounds KBrF MF SbC-IF SbBrF AsClF and AsBrF fall into the following groups:

Group I.Symmetrical and asymmetrical alkyl hydrazines and their salts, said alkyl groups containing from one to three carbon atoms.

Group IL-Organic alkyl diand poly-amines and polyamine benzenes, said alkyl groups containing from one to four carbon atoms.

Group [IL-Phenyl diazonium tetrafluoroborates and related stable phenyl diazonium salts with nitro, amino and alkyl substituents, said alkyl substituents containing from one to two carbon atoms.

Group 1V.Aluminum and boron alky-ls, said alkyl groups containing from one to three carbon atoms.

Group V.A1kyl borazanes, said alkyl group containing from one to four carbon atoms.

Group V1.Decaborane.

Group VlI.--Aminodiborane and ammonia or hydrazine or alkyl hydrazine complexes thereof, said alkyl hydrazine complexes containing alkyl groups having from one to four carbon atoms.

Group VlI1.Dialky1 magnesium compounds, said alkyl groups containing from one to four carbon atoms.

All of the aforementioned fuels combine by simple mixing with the solid complex fluoride compounds KBIF4, KI=F SbClFg, SbBrF AsClF and AsBrF to produce extremely vigorous reactions evolving large volumes of gases. While no action usually occurs immediately upon mixing the fluoride-containing oxidizer and the fuel, after an induction period from a few to as many as 30 seconds, the reaction proceeds instantaneously and explosively.

The number of active fluorine atoms present in the oxidizer will be from three to five. With an interhalide of bromine or chlorine, there will usually be 3 to 5 active fluorine atoms present and with an Iinterhalide of iodine 5 active fluorine atoms will usually be provided. The amount of fuel that will react stoichiometrically with the fluorine source is dependent upon the replaceable hydrogens in the fuel under the conditions of the reaction. Thus, the replaceable hydrogens in hydrazine hydrochloride, NH -NH -HC1Will usually be four or five in number; in decaborane (B 14) are 14 in number; etc.

Then having determined the number of active fluorines and the number of replaceable hydrogens, the amount of fuel and solid oxidizer to be employed will be such that the ratio of active fluorine to replaceable hydrogen is from about 1:1 to about 1:6. Therefore, an excess of oxidizer is usually employed.

The following example is given to more clearly illustrate the invention and is not to be construed as limiting thereto.

Example Four parts of hydrazine (NH -NH -HCl) were mixed with approximately 22.5 parts of KBrF, in an open vessel. After a short induction period of approximately 15 seconds, a combustion occurred with explosive velocity evolving large volumes of gaseous products. In less than one minute the reaction mass had been consumed leaving a small amount of inorganic residue. Further experiments with KIF SbCIF SbBrF A-sC1F and AsBrF with other fuels defined hereinbefore, resulted in similar hypergolic reactions with a negligible amount of residue, even though the ratio of replaceable hydrogen to active fluorine was varied from about 1:1 to about 1:9.

Various modifications may be made in the present invention without departing from the spirit and scope thereof and it is to be understood that We limit ourselves only as defined in the appended claims.

We claim:

'1. A method of producing a vigorous hypergolic reaction evolving large volumes of gases which comprises admixing a hypergolic oxidizer selected from the group consisting of KBrF KIF SbClFg, SbBrF ASCIFg and AsBrF and a fuel selected from the group consisting of symmetrical and asymmetrical alkyl hydrazines and their salts, alkyl diand polyamines and polyamine benzenes, phenyl diazonium tetrafluoroborates and stable phenyl diazonium salts having nitro, amino and alkyl substituents, aluminum and boron alkyls, alkyl borazanes, deca borane, aminodiborane and ammonia, hydrazine and alkyl hydrazine complexes thereof and, dialkyl magnesium compounds, the amounts of said fuel and said oxidizer in said admixture being such that the ratio of active fluorine to replaceable hydrogen is from about 1:1 to about 1:6

thereby to produce a vigorous hypergolic reaction evolving large volumes of gases.

2. A method for producing a vigorous, high velocity combustion evolving large volumes of gaseous products which comprises:

(a) providing a solid fluorine-containing hypergolic oxidizer corresponding to the formula KBrF and hydrazine hydrochloride fuel, the relative parts by weight of said oxidizer and said fuel being about 22.5 to 4,

(b) mixing said oxidizer and said fuel thereby to produce a hypergolic high velocity reaction evolving large volumes of gaseous products.

References Cited in the file of this patent UNITED STATES PATENTS 2,970,428 Zletz Feb. 7, 1961 OTHER REFERENCES 0 1959, Ordnance Engineering Handbook Oflice, Duke Univ., Durham, N.C. 

1. A METHOD OF PRODUCING A VIGOROUS HYPERGOLIC REACTION EVOLVING LARGE VOLUMES OF GASES WHICH COMPRISES ADMIXING A HYPERGOLIC OXIDIZER SELECTED FROM THE GROUP CONSISTING OF KBRF4, KIF6, SBCLF8, SBBRF8, SACIF8 AND ASBRF8 AND A FUEL SELELCTED FROM THE GROUP CONSISTING OF SYMMETRICAL AND ASYMMERTRICAL ALKY HYDRAZINES AND THEIR SALTS, ALKYL DI- AND POLYAMINES AND POLYAMINE BENZENES, PHENYL DIZONIUM TETRAFLUOROBORATES AND STABLE PHENYL DIAZONIUM SALTS HAVING NITRO, AMINO AND ALKYL SUBSTITUENTS, ALUMINUM AND BORON ALKYLS, ALKYL BORAZANES, DECABORANE, AMINODIBORANE AND AMMONIA, HYDRAZINE AND ALKYL HYDRAZINE COMPLESES THEREOF AND, DIALKYL MAGNESIUM COMPOUNDS, THE AMOUNTS OF SAID FUEL AND SAID OXIDIZER IN SAID ADMIXTURE BEING SUCH THAT THE RATIO OF ACTIVE FLUORINE TO REPLACEABLE HYDROGEN IS FROM ABOUT 1:1 TO ABOUT 1:6 THEREBY TO PRODUCE A VIGOROUS HYPERGOLIC REACTION EVOLVING LARGE VOLUMES OF GASES. 